Parametric optimization of a novel air supply device used in tunnel fire

¹ School of Building Services Science and Engineering, Xi’an University of Architecture and Technology, 710055 Xi’an, China.
² Yellow River Engineering Consulting Company Limited, 450003 Zhengzhou, China.

^* Corresponding author: liangui@xauat.edu.cn

Abstract

Tunnel widely exists in highway, subway and other underground buildings. Due to the structural limitations, the direction of evacuation is consistent with the main flow direction of smoke in the tunnel. For the design of smoke exhaust system, traditional methods aim at reducing the overall smoke concentration in the whole tunnel. However, when fire hazard occurs, rapid personnel escape requires higher visibility. In this paper, a novel air supply device designed for smoke-insulation passageway establishment and ventilation in tunnel fire is introduced. Wall-attached jet and orifice plate jet are combined in this device, which enables passageway to isolate smoke intrusion. In this study, an approach has been devised combining Response Surface Method (RSM) with numerical simulations as well as visualization experiment to get better performance of the device. Parametric optimization was conducted for the three influencing variables, i.e., the air supply volume, opening rate of orifice plate, and width of wall-attached jet. Analysis of variance (ANOVA) indicates that all the three factors are significant. Moreover, the optimal combination can be obtained within the admissible range of the three factors through response optimization. A regression equation is developed to predict the effect of the novel air supply device for any input values of the three influencing variables.